Just an FYI...many BMW owners think that their non working (new style) remote keys is caused by a failed battery...and may attempt opening the (sealed) key...and many times wind up making matters worse by cutting into the IC board or knocking off capacitors/resistors that are soldered to the board.
So be careful how far you cut into the key to open it if you decide to repair the key yourself. There's a BMW forum member (Scott from BimFest) that has been repairing a lot of BMW keys and has even posted a "wall of shame" that shows the damage some owners have done attempting to open/repair their keys...as well as why some keys have failed...due to internal damage or issues with the GM (general module)...instead of the usual assumption that the battery is dead.
I've been lucky not to need this service (knock on wood)...but you can check out his site to see if this may be the issue for you non working new style remote key. The link below is to the "wall of shame"...and at the very bottom of the page is link back to bmwgm5.com website where you can get more info on how to contact Scott and specific information for the various BMW models and GMs: <b>
(wall of shame site): www.BMWGM5.com Key Fob Wall of Shame
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